Zinc oxide ointment is a versatile skin protectant used to treat diaper rash, shield skin from sun damage, soothe hemorrhoid irritation, and support healing in minor cuts and scrapes. It works by forming a physical barrier on the skin’s surface while delivering zinc ions that reduce inflammation and speed cell repair. Available over the counter in concentrations ranging from 10% to 40%, it’s one of the most widely used topical treatments for irritated or damaged skin.
Diaper Rash
The most common use for zinc oxide ointment is treating and preventing diaper rash in infants. The ointment creates a moisture-repelling layer between the skin and wet or soiled diapers, which prevents further irritation while the skin underneath heals. You apply it with every diaper change, paying extra attention at bedtime or anytime the diaper will stay on for a longer stretch. Most cases of diaper rash improve within seven days. If the rash persists or worsens beyond that point, something else may be going on, such as a yeast infection that requires a different treatment.
Zinc oxide products for diaper rash come in a wide range of concentrations. Lower-strength formulas (10% to 20%) work well for everyday prevention, while thicker pastes at 40% are better suited for more stubborn rashes where the skin is visibly raw or inflamed. The higher the concentration, the thicker the barrier, so many parents keep a mild daily cream alongside a heavier paste for flare-ups.
Sun Protection
Zinc oxide is the active ingredient in most mineral sunscreens. Unlike chemical sunscreen filters that absorb UV rays, zinc oxide sits on top of the skin and physically reflects and scatters them. It covers the entire UV spectrum from 290 to 400 nanometers, which means it blocks both UVB rays (the ones that cause sunburn) and UVA rays (the ones that penetrate deeper and accelerate skin aging). That full-spectrum coverage is its biggest advantage: no other single sunscreen ingredient protects across the entire UV range as effectively.
Its strength in the UVA range is particularly notable. UVA rays account for roughly 95% of the ultraviolet radiation that reaches your skin, and many chemical filters don’t cover them well. Zinc oxide significantly outperforms titanium dioxide, the other common mineral filter, in this range. This makes zinc oxide sunscreens a go-to choice for people with sensitive skin or those looking for broad-spectrum protection without layering multiple chemical ingredients.
Minor Wound Healing
Zinc oxide ointment can help minor cuts, scrapes, and shallow burns heal faster. When applied to a wound, it releases zinc ions slowly into the wound fluid, maintaining steady zinc levels in the tissue over an extended period. Those ions do several useful things at once: they activate enzymes that help new skin cells migrate across the wound surface, stimulate the production of growth factors essential for building new tissue, and support the overall process of re-epithelialization, which is the body regenerating its outer skin layer.
One interesting detail is that topical zinc appears to benefit wound healing regardless of whether someone is zinc-deficient. Oral zinc supplements tend to help most in people whose zinc levels are already low. But applying zinc oxide directly to the skin bypasses that limitation because the wound tissue gets a local supply of zinc right where it needs it. People who are zinc-deficient do heal more slowly in general, but topical application benefits both groups.
Hemorrhoid and Perianal Irritation
Zinc oxide paste is a common ingredient in over-the-counter hemorrhoid treatments. It acts as a skin protectant around the sensitive perianal area, shielding irritated tissue from moisture and friction. It also has mild astringent properties, meaning it helps dry excess secretions that can make the area more uncomfortable. On top of that, zinc oxide provides a mild antiseptic effect, reducing the risk of secondary irritation from bacteria in a naturally high-moisture environment. For external hemorrhoids, it’s typically applied after cleaning the area and can be reapplied as needed throughout the day.
Acne and Oil Control
Zinc oxide has properties that make it useful for acne-prone skin, though this application is less mainstream than its other uses. Zinc ions can reduce sebum secretion from oil glands, which helps address one of the root causes of breakouts. They also prevent the abnormal buildup of dead skin cells inside hair follicles, the process that creates clogged pores in the first place.
On the antibacterial side, zinc oxide targets the specific bacteria most responsible for inflammatory acne while largely sparing the beneficial bacteria that keep skin healthy. Research on zinc oxide nanoparticles found they were 16 times more lethal to acne-causing bacteria than to the friendly microbes that make up the skin’s natural ecosystem. The antibacterial action works through multiple pathways, including triggering oxidative stress inside bacterial cells and disrupting their metabolism, which makes it harder for bacteria to develop resistance compared to a single-target antibiotic. Zinc ions also have anti-inflammatory effects that can reduce the redness and swelling of active breakouts and promote scar-free healing.
How to Choose the Right Formulation
Zinc oxide topical products come as creams, ointments, pastes, powders, and sprays, each suited to different situations. Ointments and pastes are the thickest options and provide the strongest physical barrier, making them ideal for diaper rash or protecting raw skin. Creams are lighter and easier to spread over larger areas like the face or limbs. Powders work best where you want to keep skin dry without adding a heavy layer, such as in skin folds.
Concentrations vary from about 10% up to 40%. For everyday skin protection or mild irritation, lower concentrations in the 10% to 20% range are sufficient. Higher concentrations around 40% are better for more severe irritation or when you need a thick, durable barrier that stays in place. In sunscreens, zinc oxide is typically formulated at concentrations that balance UV protection with cosmetic wearability, since higher percentages can leave a more visible white cast on the skin.
Zinc oxide ointment is generally well tolerated and safe for all ages, including newborns. True allergic reactions to zinc oxide itself are rare. If you notice the skin getting worse rather than better after applying it, the reaction is more likely to another ingredient in the product, such as a fragrance or preservative, rather than the zinc oxide itself.